
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    height: 100vh;
}

.header {
    height: 50px;
    background-color: white;
}

.content {
    display: flex;
    flex-direction: row;
    height: calc(100% - 50px);
}

.left {
    width: 20%;
    background-color: #ccc;
}

.right {
    width: 80%;
    background-color: #ddd;
}

.left ul {
    list-style: none;
}

.left ul li {
    height: 50px;
    line-height: 50px;
    text-align: center;
    border-bottom: 1px solid #ccc;
}

.left ul li a {
    text-decoration: none;
    color: #000;
    display: block;
}

.left ul li a:hover {
    background-color: #ccc;
}